1. Field of the Invention
The present invention relates to the field of capacitive sensing. In particular, the present invention is related to using a variable gain amplification system as one component to sense a change in physical phenomenon occurring at the terminals of a capacitive sensor.
2. Related Art
Capacitive sensors can sense changes related to physical phenomenon (e.g., pressure, acceleration, proximity etc) by changing the capacitance between their terminals. By sensing this change in capacitance, the change in the physical phenomenon can be measured. Using conventional techniques, however, these measurements are not as accurate as needed.
What is needed, therefore, is a method and system to more accurately measure the changes in capacitance of capacitive sensors that occur as a result of changes in physical phenomenon sensed by a sensor terminal. What is also needed is a method and system for measuring these changes that can be implemented within a single stage of an application specific integrated circuit (ASIC).